Masses of atoms or molecules were taken in comparison with other particles such as hydrogen and later carbon as the standard for comparison.... View Article
Answer: When water is added to quicklime rise in temperature is observed. This is an example of an exothermic reaction. An exothermic reaction... View Article
When a chemical change takes place with the release of heat energy, it is said to be an exothermic reaction. Exothermic reactions transfer... View Article
The speed-time graph for a particle moving at a constant speed in a straight line parallel to the time axis. In a speed-time graph, speed is... View Article
The fluid pressure of the atmosphere is measured in bars. This is equivalent to 100000 Pascal. The pascal (Pa) is the standard unit of pressure.... View Article
The average kinetic energy of a gas is directly proportional to the absolute temperature. The kinetic molecular theory of gases is a model that... View Article
Gases gave large inter-particle spaces between the molecules, this accounts for the high compressibility of gases. Gas is a state of matter,... View Article
All living plants and animals need nitrogen for their growth as it is an important constituent of proteins. Nutrition is the mode of taking... View Article
Dry hydrogen when passed over heated metals like Na, K and Ca, reacts to give their corresponding hydrides. Most of the metals do not react... View Article
Hydrogen gas is produced by active metals in reaction with dilute hydrochloric acid. When a metal reacts with an acid, it forms hydrogen gas and... View Article
Substances that are used to determine whether a particular substance is an acid or a base are called Indicator. An indicator is a dye that is a... View Article
In a group, metallic character increases and non-metallic character decreases from top to bottom. Metallic character refers to the level of... View Article
Water boils at 100oC i.e. 373 K and freezes at 0oC i.e. 273 K. The melting point of a solid is defined as the temperature at which solid... View Article
A solution in which more of the solute can be dissolved in the given solvent at a given temperature is known as an unsaturated solution. The... View Article
Oxygen is slightly heavier than air hence it is collected by the downward displacement of water. Explanation: Water displacement is a method of... View Article
Answer: A number of images are formed, when a pair of mirrors are kept at an angle to each other this is because the image formed by the first... View Article
The speed of all form of the electromagnetic wave is related by the equation c = λ ν Where c is the speed of light = 3.00 x 108 m/s, λ is the... View Article
The decay of Rocks On the Surface of the Earth Due To Exposure To the Atmosphere is Called Weathering Weathering describes the breaking down or... View Article